The present invention relates to a chopped egg product and a process for producing the same.
Various types of egg products have been produced for consumer use. Raw egg products have been prepared and frozen in order that they may be subsequently thawed and used in the same manner as fresh eggs. More recently, cooked egg products have been produced which are suitable for freezing with subsequent thawing and use. These cooked egg products are very desirable because of the convenience of simply thawing the product to permit use by the consumer. These products and processes for their production are generally described in the following U.S. Patents.
U.S. Pat. No. 3,510,315 describes a cooked egg product in which the yolks are separately cooked in a mold and placed in a larger mold in which the uncooked egg whites are placed and cooked surround the yolk. The mixture is frozen and a starch material is included in the whites to provide good freeze-thaw stability. A frozen product with an egg yolk core surrounded by cooked egg white is obtained which can easily be thawed and used by the consumer.
Improvements on the above process for the production of cooked frozen egg products are described in U.S. Pat. No. 3,598,612 in which treatment of the yolk with an oxidizing agent prevents discoloration of the interface area between the yolk and white. U.S. Pat. No. 3,598,613 describes a process in which the yolks are preheated in a jet cooker to a solid or semi-solid state, ground and then heated to form a solid yolk product. U.S. Pat. Nos. 3,798,336 and 3,711,304 describe processes and apparatus for centering of the yolk body in the egg whites before or during cooking to form a core of egg yolk concentrically surrounded by the cooked whites. These products can be conveniently thawed and sliced and easily used by the consumer without cooking and peeling of shell eggs.
The above types of cooked, frozen egg products have been extensively used by restaurants and institutions engaged in mass feeding in this country, has been the salad bar in which the customer can prepare his own salad with ingredients of his own choosing. A popular ingredient at these salad bars is chopped or diced eggs which can be sprinkled on the salad by the customer. Obviously, the cooking and chopping of eggs requires an extensive amount of preparation, in addition to the fact that chopping usually smears the yolk over the egg white particles resulting in a pasty mess the consumer does not readily associate with chopped eggs. In addition, when whole eggs are cooked, they also suffer from problems with green discoloration of the yolk surface which is visible in a chopped egg product since the particles are exposed by virtue of being chopped up or diced.
While the cooked, frozen egg products described above avoid many of the discoloration problems associated with whole eggs, nevertheless, these products also present a poor appearance if they were simply thawed and chopped or diced since the yolk readily smears onto the whites. A need, therefore, exists for a chopped frozen egg product without significant smearing of the yolks on the whites, which has a smooth texture, and may be readily thawed and used by the consumer as an ingredient in or as a condiment for foods.
U.S. application serial No. 308,709, filed Oct. 5, 1981, which is a continuation-in-part of U.S. application Ser. No. 184,585, filed Sept. 9, 1980, discloses a chopped egg product of highly desirable characteristics in which smearing of the yolk during chopping is avoided by carrying out the chopping at a critically defined temperature range. The process disclosed therein involves a single stage heating step in which the yolks and whites are separately heated to coagulate them prior to chopping.
It would be highly desirable to employ a process in which the yolks and whites can be coagulated on a continuous basis. In evaluating means for the continuous or dynamic coagulation of the yolks and whites, it was determined that the shear forces normally encountered in the dynamic heating of fluids adversely affect the texture of the yolks and the whites and if the temperature was increased during dynamic heating to effectively coagulate the yolks and whites, the yolks and whites would still maintain a soft state.
Accordingly, it was determined that dynamic or continuous heating could be used only if it was used for preheating of the yolks and whites and carried out below a critically defined product temperature. Dynamic preheating of the yolks and whites is followed by heating or maintaining the product at a given temperature under static conditions to effectively coagulate the yolks and whites to a substantially firm texture and provide the requisite texture needed for subsequent freezing and chopping of the yolks and whites.
It is, therefore, an object of the present invention to provide a cooked frozen chopped egg product which avoids significant smearing of the yolk on the chopped egg white particles.
It is also an object of the present invention to provide a cooked and frozen chopped egg product which employs a dynamic or continuous cooking process for preheating of the yolks and whites for faster cooking time with greater energy savings.
It is also an object to provide a cooked and frozen chopped egg product in which the yolk is a bright yellow with an absence of discoloration.
It is also an object to provide a cooked and frozen chopped egg product which has good freeze-thaw stability without significant deterioration of the yolks and whites during storage.
It is also an object to provide a cooked and frozen chopped egg product which has a smooth but firm texture without significant sticking or clumping of the particles of yolks and whites.
It is a further object to provide a unique process for the production of a cooked and frozen chopped egg product which meets the above objectives which is reliable and convenient to practice on a commercial basis.